Fabrication of Superconducting MgB2 Thin Films by Magnetron co-Sputtering on (001) MgO Substrates

Abstract

We fabricated superconducting MgB2 thin films on (001) MgO substrates. The samples were prepared by magnetron rf and dc co-sputtering on heated substrates. They were annealed ex-situ for one hour at temperatures between 450 • C and 750 • C. We will show that the substrate temperature during the sputtering process and the post annealing temperatures play a crucial role in forming MgB2 superconducting thin films. We achieved a critical onset temperature of 27.1 K for a film thickness of 30 nm. The crystal structures were measured by x-ray diffraction.

Synthesis of MgB2 films on Hastelloy-C276 tape with Al2O3/Y2O3/MgO/LaMnO3 buffer layers by magnetron sputtering in co-evaporation mode

“…The working pressure in the chamber was 5.3 • 10 −3 mbar, with argon used as the plasma-forming gas with a purity of 99.9999%. The base vacuum in the magnetron sputtering chamber did not exceed 8 The substrate temperature during deposition was maintained at 282 • C, chosen based on previous studies [28][29][30][31][32][33][34][35] that demonstrated the highest T c films resulted from sputtering onto substrates within the temperature range of 270…”

Crystal Structure and Properties of the Oxide-Containing Magnesium Diboride Films

“…Среди таких методов -совместное испарение компо-нент из резистивных испарителей [4], а также испарение одного из компонентов из резистивного испарителя, а другого с помощью электронной пушки [5], лазерное осаждение с последующим ex situ отжигом [6], молекулярно-лучевая эпитаксия [7], магнетронное распыление мишеней [8,9], осаждение путём гибридного физико-химического испарения (hybrid physical-chemical vapour deposition (HPCVD)) [10][11][12][13]. Каждый метод имеет преимущества и недостат-ки, для сравнения в табл.…”

Magnetic anisotropy of thin sputtered MgB2 films on MgO substrates in high magnetic fields

“…Prior investigations using Θ-2Θ x-ray diffraction measurements have shown that sputtered MgB 2 crystals are perpendicularly oriented on the surface plane independent of the choice of substrate [16]. Using the Scherrer formula, a perpendicular grain size of 7 nm could be estimated.…”